This quote is not referring to the scientific method, it is social.

If a person tries to address an emotional issue by eating chocolate or by drinking alcohol, and then the emotional issue keeps happening, and every time they address it with the same solution, then that is “insanity”. You’re doing the same thing and expecting a different result. Sure you’re not eating the same chocolate or drinking the same beer, but you’re not addressing the core of your emotional issue either.

Worth noting that this quote is incorrectly attributed to Einstein and it actually first shows up in AA literature. (Source)